High dose proton and photon-based radiation therapy for 213 liver lesions: a multi-institutional dosimetric comparison with a clinical perspective.

BACKGROUND: Stereotactic radiotherapy (SRT) and Proton therapy (PT) are both options in the management of liver lesions. Limited clinical-dosimetric comparison are available. Moreover, dose-constraint routinely used in liver PT and SRT considers only the liver spared, while optimization strategies to limit the liver damaged are poorly reported. METHODS: Primary endpoint was to assess and compare liver sparing of four contemporary RT techniques. Secondary endpoints were freedom from local recurrence (FFLR), overall survival (OS), acute and late toxicity. We hypothesize that Focal Liver Reaction (FLR) is determined by a similar biologic dose. FLR was delineated on follow-up MRI. Mean C.I. was computed for all the schedules used. A so-called Fall-off Volume (FOV) was defined as the area of healthy liver (liver-PTV) receiving more than the isotoxic dose. Fall-off Volume Ratio (FOVR) was defined as ratio between FOV and PTV. RESULTS: 213 lesions were identified. Mean best fitting isodose (isotoxic doses) for FLR were 18Gy, 21.5 Gy and 28.5 Gy for 3, 5 and 15 fractions. Among photons, an advantage in terms of healthy liver sparing was found for Vmat FFF with 5mm jaws (p = 0.013) and Cyberknife (p = 0.03). FOV and FOVR resulted lower for PT (p < 0.001). Three years FFLR resulted 83%. Classic Radiation induced liver disease (RILD, any grade) affected 2 patients. CONCLUSIONS: Cyberknife and V-MAT FFF with 5mm jaws spare more liver than V-MAT FF with 10 mm jaws. PT spare more liver compared to photons. FOV and FOVR allows a quantitative analysis of healthy tissue sparing performance showing also the quality of plan in terms of dose fall-off.

Efficacy of stereotactic body radiotherapy in oligorecurrent and in oligoprogressive prostate cancer: new evidence from a multicentric study.

BACKGROUND: The aim of the present study is to evaluate the impact of metastases-directed stereotactic body radiotherapy in two groups of oligometastatic prostate cancer (PC) patients: oligorecurrent PC and oligoprogressive castration-resistant PC (oligo-CRPC). METHODS: Inclusion criteria of the present multicentre retrospective analysis were: (1) oligorecurrent PC, defined as the presence of 1-3 lesions (bone or nodes) detected with choline positron emission tomography or CT plus bone scan following biochemical recurrence; (2) oligo-CRPC, defined as metastases (bone or nodes) detected after a prostatic-specific antigen rise during androgen deprivation therapy (ADT). Primary end points were: distant progression-free survival (DPFS) and ADT-free survival in oligorecurrent PC patients; DPFS and second-line systemic treatment-free survival in oligo-CRPC patients. RESULTS: About 100 patients with oligorecurrent PC (139 lesions) and 41 with oligo-CRPC (70 lesions), treated between March 2010 and April 2016, were analysed. After a median follow-up of 20.4 months, in the oligorecurrent group 1- and 2-year DPFS were 64.4 and 43%. The rate of LC was 92.8% at 2 years. At a median follow-up of 23.4 months, in the oligo-CRPC group 1- and 2-year DPFS were 43.2 and 21.6%. Limitations include the retrospective design. CONCLUSIONS: Stereotactic body radiotherapy seems to be a useful treatment both for oligorecurrent and oligo-CRPC.

The treatment of patients with 1-3 brain metastases: is there a place for whole brain radiotherapy alone, yet? A retrospective analysis.

AIM: To evaluate the efficacy of whole brain radiotherapy (WBRT) with or without other treatments in patients (pts) with 1-3 brain metastases (BM). MATERIALS AND METHODS: Toxicities and survival of 134 pts treated between 2009 and 2013 with WBRT alone (58 pts), WBRT plus surgery (SUR-WBRT: 42 pts) or WBRT followed by stereotactic or integrated boost radiotherapy (SRT-WBRT: 34 pts) were analyzed. Differences in toxicity (acute and late) incidence and in overall (OS), disease-free (DFS) and disease-specific survival (DSS) were evaluated (χ(2)-test, uni- and multivariate analysis). RESULTS: Pts given intensified treatments (SUR- and SBRT-WBRT) had better 3-month local response compared to WBRT alone group (p < 0.045). Better 1-year local control was evident only in SRT-WBRT pts (p < 0.035). Univariate OS analysis confirmed, as favorable prognostic factors, RPA class I (p < 0.001), GPA class III and IV (p < 0.001), single metastasis (p = 0.045), stable primary disease (p = 0.03), intensified treatment (p = 0.000), systemic therapy after radiotherapy (p = 0.04) and response of metastatic lesions (p = 0.002). At multivariate analysis, OS was better in RPA class I pts (p = 0.002), who had more aggressive radiotherapy treatments (p = 0.001), chemotherapy after radiotherapy (p < 0.001) and response to RT (p = 0.003). Response to radiotherapy (p = 0.002) and BM number (p < 0.001) resulted independently prognostic for DFS. About 60 % of patients had mild acute toxicity (G1), especially headache (51 %) and fatigue (34 %); only 2 patients (2 %) had severe (G3) headache and 5 patients (4 %) severe fatigue (G3) reversible with oral steroids. No differences were evident between the different treatment groups. Among 80 pts followed up with MRI, 12 (15 %) had leukoencephalopathy (equally distributed across subgroups) and 5 (6 %) radionecroses, 4/5 asymptomatic, 5/5 in pts given intensified treatments. CONCLUSIONS: This analysis confirms the known prognostic factors for BM, emphasizing the importance of intensified treatments in a population with favorable features.

Radiotherapy for adult medulloblastoma: Long term result from a single institution. A review of prognostic factors and why we do need a multi-institutional cooperative program.

AIM: We retrospectively analyzed our Institution experience with these patients. The endpoints of the analysis were overall survival (OS), disease-free survival (DFS), local control (LC), metastasis free survival (MFS); results were compared with the literature. BACKGROUND: Medulloblastoma in adult patients is a very rare disease; the 5 and 10-year overall survival rates range between 33-78% and 27-56%, respectively. The collection of more clinical data is strongly needed. MATERIALS AND METHODS: From September 1975 to October 2006, we treated 16 adult patients (9 males and 7 females) with a histological diagnosis of medulloblastoma. Acute and late toxicities were scored according to RTOG toxicity scale. Karnofski performance status (KPS) and neurological performance status (NPS) pre- and post-RT were reported. Median age was 27 years (range 18-53 years). All the patients received cranio-spinal irradiation, two patients were also given chemotherapy. Median follow-up period was 121.5 months. RESULTS: In January 2014, 10/16 patients were alive without evidence of disease, 6/16 died with progressive disease (1 local and spinal, 3 spinal and 2 extraneural). Ten-year LC, OS, DFS, MFS were, respectively, 84%, 67%, 60% and 59%. Univariate analysis shows that gross total resection is associated with better survival. No acute or late G3-G4 toxicity was observed. CONCLUSIONS: This experience and the analysis of the literature confirm the efficacy of postoperative RT but also the need of large datasets to better define prognostic factors and the possible role of the association of chemotherapy.

Stereotactic Body Radiation Therapy for Oligoprogressive Pleural Mesothelioma: Fine-Tuning the Optimal Doses.

There is growing evidence of a role of stereotactic body radiation therapy (SBRT) in the treatment of patients with oligoprogressive pleural mesothelioma (PM). The objective of this study was to investigate the optimal radiation therapy doses and schedules in this setting. The records of patients treated with SBRT (>5 Gy per fraction) for oligoprogression of PM at 2 institutions from June 2014 to September 2022 were reviewed. Patients were divided into 2 groups: "intermediate-dose" SBRT (i-SBRT; total dose, 30-36 Gy in 5-6 fractions) and "high-dose" SBRT (h-SBRT; total dose, 45-50 Gy in 4-8 fractions). The comparison between the 2 groups in terms of local control (LC) and toxicity was the primary endpoint of the study. Overall, 23 patients were treated for 25 pleural lesions. All had received upfront chemotherapy with platinum/pemetrexed. Fifteen patients were treated with i-SBRT and 8 patients with h-SBRT. The median equivalent dose was 40 Gy (range, 40-49.6) in the i-SBRT group and 74.46 Gy (range, 64-88) in the h-SBRT group. Six-month, 1-year, and 2-year LC were 100%, 100%, and 80% in the i-SBRT group and 100%, 100%, and 67% in the h-SBRT group, respectively (p =.94). Only 2 patients (1 for each dose group) had a recurrence in the radiation therapy field, both after experiencing a distant relapse. No severe acute and late toxicities were observed in the i-SBRT group, whereas in the h-SBRT group, 2 patients experienced G2 acute and late thoracic pain and 1 patient experienced G2 acute and G3 chronic thoracic pain. In our experience, SBRT is a safe and effective option for selected patients with oligoprogressive PM. Use of intermediate total doses keeping the dose per fraction high seems to offer an excellent LC, avoiding the risk of severe toxicity.

Impact of stereotactic body radiotherapy vs palliative radiotherapy on oncologic outcomes of patients with metastatic kidney cancer concomitantly treated with immune checkpoint inhibitors: a preliminary, multicentre experience.

PURPOSE: To explore the benefit yielded by radiotherapy (RT), we report a series of metastatic renal cell carcinoma (RCC) patients treated with concomitant RT plus Nivolumab. METHODS/PATIENTS: Patients undergoing Nivolumab treatment plus concomitant RT (ablative or palliative) were included. RT was defined Ablative if >5 Gy/fraction were delivered. RESULTS: Ablative RT intent was the only independent predictor of both progression free and overall survival (HR 3.51, 95% CI 1.6-7.5, p = 0.0012 and HR 2.8, 95% CI 0.99-8.07, p = 0.05, respectively). CONCLUSION: Ablative RT may improve oncologic outcomes in selected patients with metastatic RCC treated with Nivolumab as compared to palliative RT.

Stereotactic prostate radiotherapy with or without androgen deprivation therapy, study protocol for a phase III, multi-institutional randomized-controlled trial.

Objective: The therapeutic landscape for localized prostate cancer (PC) is evolving. Stereotactic radiotherapy (SRT) has been reported to be at least not inferior to standard radiotherapy, but the effect of androgen deprivation therapy (ADT) in this setting is still unknown and its use is left to clinical judgment. There is therefore the need to clarify the role of ADT in association with SRT, which is the aim of the present study. Methods: We present a study protocol for a randomized, multi-institutional, Phase III clinical trial, designed to study SRT in unfavorable intermediate and a subclass of high-risk localized PC. Patients (pts) will be randomized 1:1 to SRT + ADT or SRT alone. SRT will consists in 36.25 Gy in 5 fractions, ADT will be a single administration of Triptorelin 22.5 mg concurrent to SRT. Primary end point will be biochemical disease-free survival. Secondary end points will be disease-free survival, freedom from local recurrence, freedom from regional recurrence, freedom from distant metastasis and overall survival (OS); quality of life QoL and patient reported outcomes will be an exploratory end point and will be scored with EPIC-26, EORTC PR 25, IPSS, IIEF questionnaires in SRT + ADT and SRT alone arms. Moreover, clinician reported acute and late toxicity, assessed with CTCAE v. 5.0 scales will be safety end points. Results: Sample size is estimated of 310 pts. For acute toxicity and quality of life results are awaited after 6 months since last patient in, whereas, for efficacy end points and late toxicity mature results will be available 3-5 years after last patient in. Conclusion: Evidence is insufficient to guide decision making concerning ADT administration in the new scenario of prostate ultra-hypofractionation. Hence, the need to investigate the ADT role in SRT specific setting. Advances in knowledge: The stereotactic prostate radiotherapy with or without ADT trial (SPA Trial) has been designed to establish a new standard of care for SRT in localized unfavorable intermediate and a subclass of localized high risk PC.

Salvage radiotherapy for oligo-progressive malignant pleural mesothelioma.

OBJECTIVES: No standard treatment option is available for patients with unresectable malignant pleural mesothelioma (MPM) progressing after upfront chemotherapy. We aimed to explore the role of focal radiotherapy (FRT) as a treatment modality for oligo-progressive MPM. MATERIALS AND METHODS: In this retrospective study, consecutive patients pretreated with ≥1 lines of chemotherapy were included. Oligo-progressive MPM was defined as an unresectable disease with radiological progression at ≤3 sites according to a chest-abdominal contrast-enhanced computed tomography. Patients were treated with either stereotactic body radiotherapy (SBRT, ≥5 Gy per fraction) or hypo-fractionated radiotherapy (hypoRT, <5 Gy per fraction). Time to further systemic therapy (TFST) and local control (LC) after FRT were the primary endpoints. Biologically effective dose (BED) was calculated using three different alpha/beta models (1.5 Gy, 3 Gy and 10 Gy). RESULTS: From April 2006 to March 2019, 37 patients were treated on 43 pleural lesions; 16/37 (43 %) had undergone upfront multimodality treatment (MMT) including surgery. FRT was given in 22/37 (59.5 %) after one line of chemotherapy. SBRT was delivered for 26/43 lesions (60.5 %), hypoRT for 17/43 (39.5 %). Median TFST was 6 months (95 % CI 4.9-7.1). LC at 6 months and 1 year was 84 % and 76 %, respectively. Median TFST was longer in patients treated after 1 vs >1 line of chemotherapy (9 vs 4 months, p = 0.001) and in patients pretreated with MMT (6 vs 3 months, p = 0.021). Six-month LC was better in patients treated with a BED > 100 using alpha/beta 1.5 and 3. No ≥ G3 acute or late toxicities were reported. CONCLUSION: FRT was feasible in selected patients with oligo-progressive MPM, allowing delay of further systemic therapies, with no severe toxicity. FRT was more effective when performed at progression after one line of systemic therapy. Our results suggest a radio-resistant behavior of MPM.

Upfront metastasis-directed therapy in oligorecurrent prostate cancer does not decrease the time from initiation of androgen deprivation therapy to castration resistance.

The aim of the present study was to explore the potential impact of upfront metastases-directed therapy (MDT) in terms of prolongation of castration-sensitive phase in a series of oligorecurrent castration-sensitive prostate cancer (PC) patients. The present article is a multicenter retrospective study. The population of interest was castrate-sensitive oligorecurrent PC, defined as the presence of 1-3 uptakes in non-visceral sites such as bones or nodes detected by means of 18F-Choline PET/CT or 68-Gallium PSMA PET/CT. Primary endpoint was the time to castration resistance. Secondary endpoints were ADT-free survival, local progression-free survival, and overall survival. Eighty-two patients and 118 lesions were analyzed. The median time to castration resistance for the entire population of the study was 49 months (95% CI 43.6-54.4 months). The 1- and 2-year TTCR-free survival rates were 94% and 82%, respectively. At the time of analysis, 52 patients were still in the castration-sensitive phase of the disease. In this cohort of patients, the median ADT-free survival was 20 months (range 3-69 months). On the other hand, during follow-up 30 patients switched to the castration-resistant phase of disease. In this last group of patients, the median ADT-free survival was 20 months (range 4-50 months). After the ADT administration, the median castration-sensitive phase was 29 months (range 5-71 months). Castration resistance generally occurs at a median follow-up of 24-36 months following ADT. In the current study, upfront MDT does not decrease the time from initiation of ADT to castration resistance.

A neuro-oncologic challenge: the case of a large, aggressive, malignant meningioma of the skull base with paranasal sinus involvement.

BACKGROUND: Malignant meningiomas, rare tumors that account for approximately 1%-3% of all meningioma, have high recurrence, morbidity, and mortality rate and a particularly poor outcome. Surgical excision followed by adjuvant radiotherapy is the current approach for the treatment of these tumors. METHODS: In the case reported, the disease, characterized by a high proliferative index (Ki67 60%-70%), was treated with endoscopic surgery limited to the extracranial portion; then the patient underwent radiotherapy, on the residual tumor volume, to a total dose of 66 Gy delivered in 33 fractions (2 Gy/fraction) by helical intensity-modulated radiation therapy with image-guided radiotherapy daily checks (tomotherapy). RESULTS: Two and a half years after the treatment, the patient is alive and a partial response is maintained. The patient is healthy overall with grade I fatigue and grade II hearing loss as late toxicity (Common Terminology Criteria for Adverse Events 4.1). CONCLUSIONS: Within a multidisciplinary approach, new radiotherapy techniques confirm their effectiveness and reliability for the treatment of malignant meningioma.

Whole brain radiotherapy with adjuvant or concomitant boost in brain metastasis: dosimetric comparison between helical and volumetric IMRT technique.

BACKGROUND: To compare and evaluate the possible advantages related to the use of VMAT and helical IMRT and two different modalities of boost delivering, adjuvant stereotactic boost (SRS) or simultaneous integrated boost (SIB), in the treatment of brain metastasis (BM) in RPA classes I-II patients. METHODS: Ten patients were treated with helical IMRT, 5 of them with SRS after whole brain radiotherapy (WBRT) and 5 with SIB. MRI co-registration with planning CT was mandatory and prescribed doses were 30 Gy in 10 fractions (fr) for WBRT and 15Gy/1fr or 45Gy/10fr in SRS or SIB, respectively. For each patient, 4 "treatment plans" (VMAT SRS and SIB, helical IMRT SRS and SIB) were calculated and accepted if PTV boost was included in 95 % isodose and dose constraints of the main organs at risk were respected without major deviations. Homogeneity Index (HI), Conformal Index (CI) and Conformal Number (CN) were considered to compare the different plans. Moreover, time of treatment delivery was calculated and considered in the analysis. RESULTS: Volume of brain metastasis ranged between 1.43 and 51.01 cc (mean 12.89 ± 6.37 ml) and 3 patients had double lesions. V95% resulted over 95 % in the average for each kind of technique, but the "target coverage" was inadequate for VMAT planning with two sites. The HI resulted close to the ideal value of zero in all cases; VMAT-SIB, VMAT-SRS, Helical IMRT-SIB and Helical IMRT-SRS showed mean CI of 2.15, 2.10, 2.44 and 1.66, respectively (optimal range: 1.5-2.0). Helical IMRT-SRS was related to the best and reliable finding of CN (0.66). The mean of treatment time was 210 s, 467 s, 440 s, 1598 s, respectively, for VMAT-SIB, VMAT-SRS, Helical IMRT-SIB and Helical IMRT-SRS. CONCLUSIONS: This dosimetric comparison show that helical IMRT obtain better target coverage and respect of CI and CN; VMAT could be acceptable in solitary metastasis. SIB modality can be considered as a good choice for clinical and logistic compliance; literature's preliminary data are confirming also a radiobiological benefit for SIB. Helical IMRT-SRS seems less effective for the long time of treatment compared to other techniques.